摘要 |
PURPOSE: A light pickup device for different kind optical disks is provided to access all kinds of optical disks by concurring paths of light beams generated from two light sources. CONSTITUTION: The first and the second light(14, 16) are installed on a supporting plate(12) in an upper and lower directions in parallel for generating a light source to be irradiated. A light source generating unit(21) being made of an anisotropic plate(18) is arranged toward a progressing direction of a light beam from the first and the second light(14, 16). The first light source(14) generates the first light beam(TM wave) having a wave length of 635-650 nm and a vertical line polarization characteristic in the light source generating unit(21). The second light source(16) generates the second light beam(TM wave) having a wave length of 780 nm and a horizontal line polarization characteristic. An object lens(20) focuses a light beam to be irradiated on an optical disk(10). A light detecting device(22) converts a light beam reflected by the optical disk(10) into an electrical signal. A beam splitter(24) makes a light beam inputted from the anisotropic plate(18) of the light source generating unit(21) proceed to the object lens(20) through a polarizing plate(28). A collimating lens(30) progresses the first and the second light beam from the beam splitter(24) to the object lens(20) in parallel. A sensor lens(30) focuses the light beam from the beam splitter(24) on a surface of the light detecting device(22).
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